Data Encryption in 2025: Algorithms, Use Cases, and Challenges

What Is Data Encryption? 

Data encryption is the process of converting plaintext into unreadable ciphertext using a mathematical algorithm and a key, making data secure from unauthorized access. It protects data at rest, in use, and in transit by rendering it unintelligible without the proper key to decrypt it. Encryption has three key aspects:

• Plaintext to ciphertext: Encryption takes human-readable data (plaintext) and transforms it into a jumbled, unreadable format called ciphertext using a secret key. 
• Decryption: To access the data again, a decryption key is used with the same algorithm to convert the ciphertext back into plaintext. 
• Key management: Protecting and managing the encryption key is crucial, as losing the key means losing access to the encrypted data.

Types of encryption include:

• Symmetric encryption: Uses a single, secret key for both encrypting and decrypting data. 
• Asymmetric encryption: Employs a pair of keys: a public key for encrypting data and a private key for decrypting it.
• Quantum-safe encryption: Encryption based on algorithms that are impervious to decryption by quantum computers.

Encryption underpins many security technologies such as SSL/TLS for websites, encrypted emails, and disk encryption for physical devices. Without encryption, any intercepted data remains vulnerable to unauthorized reading, manipulation, or theft.

This is part of a series of articles about data security (coming soon)

Why Is Data Encryption Important? 

Data encryption protects sensitive information from unauthorized access, tampering, and theft. As cyber threats increase and regulatory demands tighten, encryption has become crucial for maintaining data security and compliance:

• One key benefit of encryption is that it safeguards data integrity. By ensuring that data remains unchanged during storage or transmission, encryption helps detect and prevent tampering and corruption, whether accidental or malicious. Encrypted data can also confirm authenticity, signaling that it hasn’t been modified by unauthorized parties.
• Encryption also supports compliance with industry regulations. Standards like HIPAA in healthcare and PCI DSS in finance require organizations to protect sensitive data, often explicitly mandating encryption. By adopting encryption, businesses reduce the risk of fines and legal exposure due to non-compliance.
• Another key function of encryption is protecting data at rest: Information stored on devices, servers, or databases. Even if physical or remote access is gained by a malicious actor, encrypted data remains unreadable without the appropriate key.
• Encryption is equally important for securing data in transit, such as when it’s sent across networks or between devices. This is particularly vital in environments with mobile or remote workforces, where sensitive information frequently travels outside controlled networks.
• Finally encryption is a foundation of secure cloud storage. As organizations shift to cloud-based infrastructure, encryption ensures that stored data is shielded from unauthorized access, even if cloud servers are compromised.

How Data Encryption Works and Types of Encryption Keys 

Data encryption uses algorithms to scramble readable data into an unintelligible form. The encryption process involves feeding plaintext and an encryption key into a cryptographic algorithm, which outputs ciphertext. This ciphertext can only be reversed if the authorized party possesses the correct decryption key. 

Two main types of encryption exist: symmetric encryption, where the same key is used for both encryption and decryption, and asymmetric encryption, which uses a public key for encryption and a private key for decryption. In practice, most secure communication protocols use a hybrid approach, combining asymmetric and symmetric encryption to balance security and performance.

Symmetric Encryption

Symmetric encryption uses the same key for both encrypting and decrypting data. The sender and recipient must both possess the secret key and keep it confidential. Algorithms such as AES (Advanced Encryption Standard) and DES (Data Encryption Standard) are common examples. The main advantage of symmetric encryption is its efficiency and speed, making it suitable for encrypting large volumes of data or data in real-time applications.

However, secure key distribution remains a significant challenge: both parties must exchange the key over a secure channel. If the key is intercepted or leaked, the encrypted data can be compromised. Therefore, symmetric encryption is often used in conjunction with asymmetric encryption, the latter providing secure key exchange mechanisms.

Asymmetric Encryption

Asymmetric encryption uses two mathematically related keys: a public key for encryption and a private key for decryption. The public key can be distributed openly, allowing anyone to encrypt data; only the holder of the private key can decrypt it. This approach solves the problem of secure key distribution found in symmetric encryption. Notable algorithms include RSA, elliptic curve cryptography (ECC), and Diffie–Hellman.

Despite its advantages, asymmetric encryption is computationally more intensive and slower than symmetric encryption. As a result, it is typically used for securing small data exchanges, such as digital signatures or session key exchanges, rather than encrypting large datasets directly. 

Quantum Encryption

Quantum encryption leverages principles of quantum mechanics to secure data, most notably through quantum key distribution (QKD). QKD allows two parties to generate and share a cryptographic key with security guaranteed by the laws of physics rather than computational hardness. Any attempt to intercept or measure quantum particles, such as photons, disturbs their state and reveals the presence of an eavesdropper.

Unlike classical encryption, which can be broken if attackers gain enough computing power, quantum encryption offers provable security under current physical models. However, practical deployment is limited. QKD requires specialized hardware, is constrained by distance in fiber-based networks, and has high implementation costs.

Common Data Encryption Algorithms

Symmetric Encryption Algorithms

Symmetric encryption relies on a single secret key for both encryption and decryption. It is fast and efficient, especially for encrypting large datasets. Common and current symmetric encryption algorithms include:

AES (Advanced Encryption Standard)

• Status: Industry standard (NIST-approved)
• Key Sizes: 128, 192, or 256 bits
• Use Cases: VPNs, SSL/TLS, disk encryption, file encryption
• Strengths: High performance and strong security; widely used and well-vetted

ChaCha20

• Status: Modern stream cipher, standardized by IETF
• Use Cases: TLS (especially in mobile/low-power devices), OpenSSH
• Strengths: Faster and more secure than older ciphers like RC4; highly efficient on software

Triple DES (3DES)

• Status: Deprecated for many applications due to vulnerabilities
• Key Sizes: 112 or 168 bits
• Use Cases: Legacy systems only
• Weaknesses: Slower and less secure than AES; not recommended for new applications

Blowfish and Twofish

• Status: Secure but less widely adopted than AES
• Use Cases: Embedded systems, disk encryption
• Strengths: Good performance, free and unpatented

Asymmetric Encryption Algorithms

Asymmetric (public-key) encryption uses a pair of keys: one public and one private. It is often used for secure key exchange, digital signatures, and encrypting small data blocks.

RSA (Rivest–Shamir–Adleman)

• Key Sizes: 2048-bit (minimum recommended), 3072-bit, 4096-bit
• Use Cases: Email encryption (PGP), SSL/TLS, digital signatures
• Weaknesses: Large key sizes, slower than modern alternatives

Elliptic Curve Cryptography (ECC)

• Popular Curves: Curve25519, secp256k1, P-256
• Strengths: Smaller key sizes with equivalent security to RSA; faster performance
• Use Cases: HTTPS, blockchain (e.g., Bitcoin), secure messaging (Signal)

Diffie–Hellman (DH) and ECDH (Elliptic Curve Diffie–Hellman)

• Use Cases: Secure key exchange protocols
• Modern Variants: ECDH (based on ECC) is widely used in TLS/SSL
• Strengths: Efficient and secure when using modern parameters

Quantum-Safe Encryption Algorithms

Quantum encryption aims to secure data against the capabilities of quantum computers, which can potentially break classical cryptography (especially RSA and ECC). It includes:

Quantum Key Distribution (QKD)

• How It Works: Uses quantum physics (entanglement, no-cloning theorem) to securely distribute encryption keys
• Protocols: BB84, E91
• Deployment: In research and early commercial use (e.g., government, banking sectors in China and Europe)

Post-Quantum Cryptography (PQC)

• Overview: Classical cryptographic algorithms that are believed to be resistant to quantum attacks
• Examples:
  • Kyber: Lattice-based encryption (NIST-selected for standardization)
  • Dilithium: Digital signature algorithm (also NIST-recommended)
  • NTRU: Fast lattice-based algorithm with long-standing academic support
• Status: Some PQC algorithms have already been standardized by NIST
• Goal: Replace RSA/ECC before large-scale quantum computers become viable

Key Data Encryption Use Cases 

Secure Web Communication

Data encryption is essential for secure websites, especially those handling personal and financial data. Hypertext Transfer Protocol Secure (HTTPS) uses SSL/TLS encryption to protect data exchanged between a user’s browser and the web server. This ensures that sensitive information like login credentials, banking details, or personal messages cannot be intercepted or manipulated during transmission.

Implementing website encryption also helps establish user trust. Security certificates validated by certificate authorities assure visitors that their connections are encrypted and authentic. Search engines also prioritize secure sites, making encryption an integral part of both security and business success online.

Email Security

Encryption plays a vital role in safeguarding email communications. Without encryption, emails are vulnerable to interception as they travel through different networks and servers before reaching the recipient. Protocols such as S/MIME and PGP enable users to encrypt message contents and attachments, ensuring only intended recipients can read the email.

Beyond content privacy, email encryption can also confirm the identity of senders and verify message integrity. Specialized solutions automate encryption for businesses, reducing the risk of data loss and regulatory non-compliance. As phishing and business email compromise attacks rise, encrypted email remains a key defense layer.

Mobile Devices

With growing use of smartphones and tablets for personal and business activities, encrypting data on mobile devices has become critical. Mobile operating systems like iOS and Android offer built-in encryption to protect data at rest, such as stored emails, texts, application data, and photos. This protects sensitive information if a device is lost or stolen, preventing unauthorized access.

Mobile device management solutions enable organizations to enforce encryption policies, remotely wipe devices, and separate work from personal data. App developers are encouraged to use secure APIs for data transmission and storage, ensuring robust security across the mobile ecosystem. As the proliferation of mobile threats continues, device-level encryption remains a mandatory safeguard.

Unmanaged Corporate Devices

Unmanaged corporate devices, such as laptops or desktops outside centralized IT control, pose significant risks when handling sensitive data. Without enforced security policies, these devices may lack full-disk encryption, secure storage mechanisms, or up-to-date patches. If lost, stolen, or compromised, unencrypted data on these systems can be directly accessed, leading to potential data breaches. Encrypting data at rest on unmanaged devices mitigates this risk, ensuring that even if attackers gain physical access, the information remains inaccessible without proper authentication.

Organizations can strengthen protection by deploying solutions that enforce encryption policies remotely, such as endpoint encryption software with centralized reporting. Coupled with key escrow or recovery mechanisms, this approach ensures encrypted data remains accessible to authorized personnel while staying secure against misuse. In distributed or hybrid work environments, enforcing encryption on unmanaged corporate devices becomes a cornerstone of data security, preventing leaks from devices operating outside standard IT oversight.

Cloud and Multi-Tenant Environments

Encryption is vital in cloud and multi-tenant environments where data belonging to multiple organizations or users may share the same infrastructure. Encrypting files, databases, and virtual machine disks helps prevent unauthorized access by malicious insiders or compromised cloud services. Cloud providers often offer built-in encryption options, but customers remain responsible for managing keys and ensuring proper configuration.

End-to-end encryption and bring your own key (BYOK) models give organizations extra control in the cloud, providing assurance that only they can decrypt their data. Regulatory compliance further necessitates strong encryption for cloud-stored sensitive data. With threats from both external and internal actors, cloud encryption forms a critical pillar of a robust cloud security posture.

Data Encryption Challenges 

Here are some of the key challenges organizations face when managing encryption systems.

Key Management Complexity

Managing encryption keys securely is one of the most challenging aspects of any encryption strategy. The risk is that if keys are lost, data becomes permanently irretrievable. Conversely, stolen or improperly disclosed keys allow attackers to decrypt protected information without detection. Key rotation, storage, distribution, and retirement all introduce operational complexity. 

Organizations may use dedicated hardware security modules (HSMs), vaults, or cloud-based key management services to centralize and protect keys. However, implementing and integrating these solutions requires expertise and careful planning to avoid misconfigurations or workflow disruptions. Regulatory requirements may mandate strict key lifecycle management, adding further pressure to organizations handling sensitive data.

Performance and Latency Overheads

Encryption and decryption are computationally intensive operations. Particularly in high-transaction environments such as e-commerce, payments, or video streaming, encryption can introduce noticeable performance and latency overhead. Older algorithms or inefficient implementations can exacerbate these issues, affecting user experience and business operations. 

Mitigating these impacts requires tuning encryption algorithms, leveraging hardware acceleration, and offloading cryptographic processes wherever feasible. Choosing the right encryption technology is also essential: asymmetric cryptography, though more secure for key exchange, is much slower than symmetric algorithms and should not be used for bulk data processing. Balancing performance and security is a constant operational challenge.

Data Lifecycle Management

Data encryption is not a one-time activity; it must account for the entire data lifecycle—creation, storage, use, transmission, archiving, and destruction. Different stages require different levels of protection, and lapses at any point can lead to exposure. For example, data decrypted temporarily in memory can be vulnerable to attacks targeting RAM or swap space. 

Automating encryption policies that trigger at key stages of the data lifecycle is essential for minimizing security gaps. Data retention, archival, and secure disposal procedures must integrate with encryption systems to prevent orphaned or accessible plaintext data. Continuous monitoring and policy enforcement are required to cope with evolving threats and dynamic data environments.

Best Practices for a Successful Data Encryption Strategy 

1. Balance Security with Usability

Strong encryption policies can hinder usability if not properly aligned with workplace habits and system requirements. Excessive prompts for manual key entry or complex workflow changes can drive users to circumvent security controls. It’s crucial to design encryption implementations that provide robust protection while remaining transparent and easy to use for authorized personnel.

Usability benchmarks, such as seamless authentication and automatic encryption-decryption mechanisms, can foster adoption and keep productivity high. User training and awareness programs can also reduce mistakes or accidental exposures. The best approach balances security mandates and practical user interaction for sustained effectiveness.

2. Secure Backups and Disaster Recovery

Backup data is a prime target for cybercriminals, as unencrypted backups can leak sensitive information in the event of a breach. Encrypting backups, whether on-site, off-site, or in the cloud, ensures data remains protected against theft or loss. Recovery processes should also enforce decryption only by authorized users.

Regularly testing backup restoration procedures while verifying decryption integrity is vital for preparedness. Organizations should treat backup encryption keys with the same diligence as primary data keys, maintaining offsite copies and strict access controls. Secure backups help minimize downtime and data loss in disaster scenarios while ensuring compliance with data protection requirements.

3. Implement Strong Identity and Access Controls

Encryption alone cannot protect data if unauthorized personnel can access decryption keys. Robust identity and access management (IAM) frameworks define who can access what information and under what conditions. Multi-factor authentication, role-based access control, and just-in-time permission models help limit key access to only those who need it. Continuous monitoring and logging of access attempts further strengthen controls.

Integrating IAM with encryption systems ensures auditing and regulatory tasks are simplified, while also enabling rapid incident response. Strong IAM underpins every effective encryption strategy by ensuring that only authorized actions are possible on encrypted data.

4. Automate and Integrate Encryption

Manually applying encryption leads to human errors and gaps in protection. Automation across endpoints, databases, networks, and cloud services ensures that data is encrypted by default and at every critical juncture. Integration with DevSecOps pipelines, storage solutions, and SaaS products extends encryption across hybrid environments.

Automated monitoring tools can detect misconfigurations or non-compliance, triggering remediation actions rapidly. By embedding encryption into business processes and IT infrastructure, organizations reduce the risk of unencrypted data exposure while easing compliance burdens. Automation proves essential as environments scale and diversify.

5. Use Encryption to Secure the BYOD Environment

The proliferation of bring-your-own-device (BYOD) policies increases the complexity of data protection. Personal devices often lack standardized security controls, making centralized encryption enforcement difficult. Organizations should deploy mobile device management (MDM) solutions that enforce device-level encryption and monitor the security posture of each connected device.

Regular audits, policy updates, and endpoint security checks ensure that sensitive data does not leak via unmanaged apps or unencrypted storage. Containerization techniques can further isolate corporate and personal information, allowing employees to use their devices without compromising organizational security. Encrypted workspaces are critical for mitigating BYOD-associated risks.

Learn more in our detailed guide to data security best practices 

Enforcing Encryption in BYOD Environments with Venn

With Venn’s Blue Border™, encryption is built directly into the way employees and contractors access work applications and data – no matter where they are or what device they’re using.

Similar to an MDM solution but for laptops – work lives in a company-controlled Secure Enclave installed on the user’s PC or Mac, where all data is encrypted and access is managed. Work applications run locally within the Enclave – visually indicated by Venn’s Blue Border™ – protecting and isolating business activity while ensuring end-user privacy. This approach allows employees to use personal devices without risking exposure of company data.

Key Venn Features for Data Encryption on BYOD laptops:

• Encrypted workspace by default – Every corporate application and file is protected without extra steps for the user
• Context-aware access controls – Encryption policies adjust based on user identity, device status, and network environment
• Zero Trust enforcement – Data access is continuously verified, limiting the risk of breaches even if a device is lost or compromised
• Full session logging – Every interaction within the secure enclave is tracked for compliance and auditing

You can book a quick demo here